Low power and Lossy Networks (LLNs), e.g., sensor networks, have a myriad of applications, such as Smart Grid and Smart Cities. Various challenges are presented with LLNs, such as lossy links, low bandwidth, battery operation, low memory and/or processing capability, etc. One example routing solution to LLN challenges is a protocol called Routing Protocol for LLNs or “RPL,” which is a distance vector routing protocol that builds a Destination Oriented Directed Acyclic Graph (DODAG, or simply DAG) in addition to a set of features to bound the control traffic, support local (and slow) repair, etc. The RPL architecture provides a flexible method by which each node performs DODAG discovery, construction, and maintenance.
One of the main challenges in LLNs is to optimize the use of scare network resources such as the network capacity considering the very limited bandwidth available in the network. Since a significant proportion of the traffic is point-to-multipoint (P2MP) and multipoint-to-point (MP2P), bandwidth limitation becomes a limiting factor closer to the data collection point (e.g., a sink) where traffic increases, thus leading to congestion, quality of service (QoS) degradation, and also battery depletion when nodes are battery operated.